Such gearshift devices are preferably used in heavy industrial motor vehicles and omnibuses. Such devices have been disclosed in DT 25 02 578 C3. Here, the forward gears are situated in a swivel plane of the shifting lever and the reverse gears in another swivel plane parallel therewith. In automatically shifting transmissions, the automatically shifting driving steps are conveniently situated in one swivel plane and the gears to be manually shifted in the other.
Especially in construction site vehicles, it is required that a quick shift from one gear to the other and in the opposite direction of travel be possible. Inadmissible downshifts and reversing operations at too high traveling speeds must be avoided.
Although the gearshift device known already has a detent solenoid which is activated in accordance with the shifting position and the correspondingly admissible speed, the control of said detent solenoid requires a high cost of control in order to ensure that the shifting cycle is not hindered in the admissible limits.
The problem to be solved by the invention is to design a downshift lock for a gearshift device so that it is easier to control, without hindering the gearshifting cycle.